I understand that the axle spacing for Alco tri-mounts is 6' 11" and 5' 7" from the middle axle with the bolster offset 22". What commercially available HO scale models come with this type of truck? From what I can tell, BLI's RSD-15 does, but I'm not sure about the other Alco's (c628, c630, etc.)

This would be for a kitbash project I have in mind which I'll talk about more later.

not exactly sure about the axle spacing, but the ge version of the trimount has much thicker drop equalizers than the alco version, with a noticeable taper toward the center axle. they are good for u25c, early u28c, and not much else. possibly used under the e33 and 3\e44 electrics, but i don't have photos available....

I just uncovered a mass of detail parts and cannon EN22 motors, and many sets of different trucks. I know some are alco trucks due to the odd spacing. what do you need? This is all stock from E&P Associates from a few years ago. Some of the parts are fans, dynamic brakes, fans, detail parts, antenna, plows, beacons, hoses, ect